Dash vapour on screen

Hi there, I have a 328 GTS and notice smearing on the inside of the windscreen. I was advised that the cause was oil vapour from the dash material? Anyone had something similar? ideas on how to treat this? Many thanks.

 

I’ve experienced this on my 308 and also thought it was due to out gassing of the dash material, but never had any real confirmation. Curious what others here will have to say.

I just try to diligently clean with a good quality glass cleaner (Stoner makes a great one). The haze/smear will eventually return, so I just stay on top of it.

Ruben

 

No, it's the cleaner/protectant that you use. Armourall is used here, and on a hot day, the inside of the screen gets a coating. It also lets the screen fog up more easily. So (a) don't use too much of the stuff and wipe it off thoroughly, and (b) wipe the screen with warm water and dish washing liquid, then fresh warm water, then dry with a paper towel

 

These cars are over 25 years old now. There would be zero gassing from the vinyl material from the upper dashboard. More likely as Patrick mentioned overspray from a cleaner used in the past.

 

My 308 is from 1978, so it's 40 years old and 20 of'em in my posession. I never used any ArmourAll for the dahboard, but nevertheless when the sun shines through the windscreen on the dashboard for one day, the screen gets the foggy haze. Very annoying, especially when driving home in the evening against the low standing sun. So it seems that the dashboard cover material is still gasing!

 

My understanding is that vinyl will continue to off-gas through its lifetime. Off-gassing can be reduced by using a vinyl dressing with a sun protection factor. This only reduces the rate; it doesn't stop the off-gassing or replenish the esters in the vinyl. A good vinyl dressing will cite its SPF on the bottle.

Any conditioners in the car can vaporize and deposit on the window glass. This could include the leather conditioner on the seats as well as vinyl dressing.

I have to worry about this more on my antique BMW which has a hard vinyl dashboard which is infamous for cracking over time.

Again, I am not an expert; this is just what I have read (… and maybe I read it on the internet!)

 

Spot on information! Vinyl will off-gas for life. I carry a microfiber towel in my door pocket and just wipe down the glass whenever the car has sat in the sun.

 

Every car I've ever owned does this,. It's what dashboards do!

 

I just had a brand new windshield put on my QV five months ago and noticed the same hazyness happening again just like before specially if I drive it on a warm day, it’s got to be the dashboard.

 

Thanks Brian, I will look out for a vinyl dressing with SPF. Regards, John

 

I have a 328 with a leather dash with the same issue and just clean it regularly with a clean towel. My new 3 series BMW has this issue as well like all cars but in the 328/308 the slanted position likely attracts more dirt/moistre/vapour.

 

I got one of those dash covers that are supposed to cut the glare when you drive. It's works fine for that, but the real benefit is that when I park out in the sun, I throw the dash cover on and it keeps the haze from appearing.

 

I figure v.o.c.s and such from the rest of the cabin follow the convection current from the sun heating the dash, adding to the gases emanating from the dash itself and depositing on the glass as well.

 

https://www.walmart.com/ip/303-30308-Aerospace-Protectant-for-Plastic-Vinyl-and-Rubber-16-oz/45626471